Thanks so much for all the helpful replies.
She has cut down a bit on the scratching and paw licking, without me changing anything. Maybe she's adapting to her new environment...and change of diet? I forgot to mention she was on Science Diet when she came and I immediately changed her over to Wellness...gradually, of course.
I can barely feel her ribs...faintly, under about 3/8" of soft Zoey.
She has quite a deep chest...I'm guessing that's the Chihuahua in her...